Applicant claims priority under 35 U.S.C. xc2xa7119 of Austrian Application No. GM 224/99 filed Apr. 6, 1999. Applicant also claims priority under 35 U.S.C. xc2xa7120 of PCT/AT00/00077 filed Apr. 4, 2000. The international application under PCT article 21(2) was not published in English.
The invention relates to a spreading device of the type outlined in the generic part of claim 1.
A spreading tool is known from U.S. Pat. No. 5,810,333 A, consisting of a telescopic arrangement of two tubes, an outer tube having an end face with a ram member inside which the inner tube, also having a ram member, is slidably mounted. The outer tube has an opening in the wall for inserting spreadable tips of a spreading drive. In order to perform a spreading operation, the spreading tool is positioned between the parts to be spread and the telescopic arrangement operated with an independent spreading drive. The resultant spreading path is dependent on the opening width of the lever arms of the spreading drive and is therefore relatively small. In order to produce larger spreading widths, a spreading ram which can be adjusted in stages in an axial direction relative to the inner tube has to be fitted and the spreading drive operated again after each adjustment, requiring a considerable amount of time to achieve adequate spreading widths.
Accordingly, the objective of the invention is to propose a device which, being of the standard size and weight for this type of rescue equipment, has an expandable range which is such that the attainable opening widths correspond to the regulations governing xe2x80x9cman openingsxe2x80x9d, stipulated in the regulations governing pressurised containers, for example.
This objective is achieved by the invention due to the characterising features of claim 1. The surprising advantage of this arrangement is that by providing a pressure ram assembly operable by means of pivot arms, the spreading range of the extrication tool is doubled without the need to use more powerful drives and incurring only a slight increase in the weight of the device.
An embodiment of the type defined in claim 2, which has pressure rams adjustable by a guiding system, is of advantage because the expansion forces to be applied to the peripheral regions of the wall and structural areas, which are generally irregular relative to one another, can be exactly aligned regardless of the force components occurring as a result of the reaction forces which act on the predetermined longitudinal central axis determined by the longitudinal central axis of the pressure ram assembly.
Claim 3 describes another embodiment which has the advantage of producing high resistance torques in the guiding system which counteract any buckling of the pressure ram assembly.
The advantageous embodiments described in claims 4 and 5 offer a technically simple and inexpensive way of obtaining an axially stable arrangement.
Claim 6 describes an advantageous embodiment whereby movement is exactly dependent on the telescopic assembly of sections.
A preferred embodiment is also described in claim 7, whereby standard extrication apparatus can be optionally retrofitted with a pressure ram assembly in order to increase the expandable range.
Claim 8 describes an other advantageous embodiment which enable a high force to be applied and a durable, uninterrupted coupling to be obtained.
A preferred embodiment is described in claim 9, whereby any torsional forces which might occur, as is the case when spreading irregularly shaped wall elements, materials, etc., are absorbed.
Standard tubes are used for the advantageous embodiment described in claim 10, making this design inexpensive.
As a result of an advantageous embodiment of the type described in claim 11, the individual sections can be prevented from twisting without the need for additional anti-twisting means.
Other possible embodiments are described in claims 12 to 14, by means of which the pressure ram assembly can be fixed in the expanded position at the end of a spreading operation, thereby not active or when the spreading tool is removed.
The embodiment described in claim 15 ensures that the regions impeding extrication of a person are sufficiently spaced apart to comply with the measurements specified in safety standards and regulations.
Finally, an embodiment of the type described in claim 16 is of advantage because it provides a non-slip support for the spreading tool on sheet metal and plastics, which generally have very smooth surfaces.